123871-53-4Relevant academic research and scientific papers
Pd(II) complexes of novel phosphine ligands: Synthesis, characterization, and catalytic activities on Heck reaction
Altan, Orhan,Serinda?, Osman,Say?n, Koray,Karaka?, Duran
, p. 993 - 999 (2016)
Novel phosphine oxides, (((3-methylpyridin-2-yl)amino)methyl)diphenylphosphine oxide (1) and diphenyl((pyrazin-2-ylamino)methyl)phosphine oxide (2), were synthesized and characterized. Phosphines ligands (3 and 4) were obtained by the reduction of 1 and 2 with AlH3, monitored by31P NMR spectroscopy. Pd(II) complexes of 3 and 4 were synthesized and characterized (5 and 6). The catalytic activity of 5 and 6 was tested on the reaction of styrene with both activated and deactivated aryl bromides in air. The results of the catalytic experiments were discussed through DFT calculations.
Ionic liquid-mediated benzoyl transfer-coupling in the Suzuki and Sonogashira reactions and aryl transfer-coupling by decarbonylative Heck reaction, using N-Benzoyl-saccharin (NBSac) as reagent
Malunavar, Shruti S.,Sutar, Suraj M.,Prabhala, Pavankumar,Kalkhambkar, Rajesh G.,Laali, Kenneth K.
, (2020/05/18)
The efficacy of N-benzoyl-saccharin (NBSac) as reagent for selective benzoyl transfer-coupling in the Suzuki reaction in BMIM-IL/[PAIM][NTf2] as solvent/base, and in the Sonogashira reaction employing guanidinium-IL (GIL) as solvent, are demonstrated. Decarbonylative aryl transfer-coupling occurs in the Heck reaction employing GIL as solvent. The reactions are catalyzed by Pd(OAc)2 or NiCl2(dppp), are performed under mild conditions in good yields, and have the potential for recycling/reuse of the IL solvent. Collectively, these methods provide facile access to diverse libraries of diarylketones, keto-ethynes and diaryl-ethenes.
1-Aryltriazenes in the Suzuki, Heck, and Sonogashira Reactions in Imidazolium-ILs, with [BMIM(SO3H)][OTf] or Sc(OTf)3 as Promoter, and Pd(OAc)2 or NiCl2·glyme as Catalyst
Sutar, Suraj M.,Savanur, Hemantkumar M.,Malunavar, Shruti S.,Prabhala, Pavankumar,Kalkhambkar, Rajesh G.,Laali, Kenneth K.
, p. 6088 - 6093 (2019/09/17)
1-Aryltriazenes, the protected and more stable form of aryl-diazonium species, can be conveniently unmasked with Br?nsted acidic-IL or Sc(OTf)3 and coupled with a host of aryl/heteroaryl boronic acids, styrenes, and aryl/alkyl acetylenes in the Suzuki, Heck and Sonogashira reactions in one-pot and in respectable isolated yields, by using palladium or nickel catalyst in readily available imidazolium ILs as solvent, under mild conditions. The scope of these reactions are explored, and the potential for recovery/reuse of the IL solvent is also addressed.
Piperidine-appended imidazolium ionic liquid as task-specific basic-IL for Suzuki and Heck reactions and for tandem Wittig-Suzuki, Wittig-Heck, Horner-Emmons-Suzuki, and Horner-Emmons-Heck protocols
Savanur, Hemantkumar M.,Kalkhambkar, Rajesh G.,Laali, Kenneth K.
, p. 150 - 161 (2017/06/30)
Facile, high yielding, one-pot methods for the synthesis of a library of diversely substituted bi-aryls, diarylethenes, and aryl-enoates, via Suzuki and Heck reactions, and by sequential Wittig-Suzuki, Wittig-Heck, Horner-Emmons-Suzuki, and Horner-Emmons-Heck reactions are reported. The reactions employ piperidine-appended imidazolium ionic liquid [PAIM][NTf2] as a task-specific basic-IL, butyl-methyl-imidazolium ionic liquid [BMIM][X] (X?=?PF6, BF4) as solvent, and catalytic amounts of Pd(OAc)2 with no other additives. Wittig and Horner-Emmons reactions are effected by reacting substituted benzaldehydes with 4-bromobenzyl-PPh3 (or bromomethyl-PPh3) phosphonium salts, or diethylphosphonate with bromobenzaldehydes respectively, to form the corresponding ethenes. Subsequent cross-coupling reactions are accomplished by addition of aryl-boronic acid or phenyl-ethenes along with Pd(OAc)2 to bring about the aforementioned hyphenated transformations. The feasibility to perform double-olefination via Wittig and Horner-Emmons reactions with dialdehydes to form highly conjugated bis-styryl and bis-enoate compounds is also shown. The [BMIM][X] solvent is recycled and reused.
Nickel-Catalyzed Alkoxy–Alkyl Interconversion with Alkylborane Reagents through C?O Bond Activation of Aryl and Enol Ethers
Guo, Lin,Liu, Xiangqian,Baumann, Christoph,Rueping, Magnus
supporting information, p. 15415 - 15419 (2016/12/03)
A nickel-catalyzed alkylation of polycyclic aromatic methyl ethers as well as methyl enol ethers with B-alkyl 9-BBN and trialkylborane reagents that involves the cleavage of stable C(sp2)?OMe bonds is described. The transformation has a wide substrate scope and good chemoselectivity profile while proceeding under mild reaction conditions; it provides a versatile way to form C(sp2)?C(sp3) bonds that does not suffer from β-hydride elimination. Furthermore, a selective and sequential alkylation process by cleavage of inert C?O bonds is presented to demonstrate the advantage of this method.
Iron pincer complex catalyzed, environmentally benign, E-selective semi-hydrogenation of alkynes
Srimani, Dipankar,Diskin-Posner, Yael,Ben-David, Yehoshoa,Milstein, David
supporting information, p. 14131 - 14134 (2014/01/06)
Ironing out hydrogenation: For the first time, an iron catalyst provided chemo- and stereo-selective semi-hydrogenation of alkynes to E-alkenes. This efficient, atom-economical reaction is catalyzed by a novel acridine-based PNP iron pincer catalyst and exhibits excellent functional group tolerance under mild, neutral, environmentally benign reaction conditions. Copyright
Palladium-catalyzed cross-coupling reactions of potassium alkenyltrifluoroborates with organic halides in aqueous media
Alacid, Emilio,Najera, Carmen
supporting information; experimental part, p. 2321 - 2327 (2009/07/18)
Potassium vinyl and alkenyltrifluoroborates are cross-coupled with aryl and heteroaryl bromides using 1 mol % Pd loading of 4-hydroxyacetophenone oxime derived palladacycle or Pd(OAc)2 as precatalysts, K 2CO3 as base, and TBAB as additive and water reflux under conventional or microwave heating to afford styrenes, stilbenoids, and alkenylbenzenes. These borates can be cross-coupled diastereoselectively with allyl and benzyl chlorides using KOH as base in acetone-water (3:2) at 50°C and 0.1 mol % Pd loading, giving the corresponding 1,4-dienes and allylarenes, respectively. These simple phosphine-free reaction conditions allow the palladium recycling from the aqueous phase during up to five runs by extractive separation of the products, which contain 58-105 ppm of Pd.
Homeopathic ligand-free palladium as a catalyst in the heck reaction. A comparison with a palladacycle
de Vries, Andre H. M.,Mulders, Jan M. C. A.,Mommers, John H. M.,Henderickx, Huub J. W.,de Vries, Johannes G.
, p. 3285 - 3288 (2007/10/03)
(Matrix presented) Ligand-free Pd(OAc)2 can be used as a catalyst in the Heck reaction of aryl bromides as long as the amount of catalyst is kept between 0.01 and 0.1 mol %. At higher concentrations palladium black forms and the reaction stops. The actual catalyst is monomeric. Palladacycles merely serve as a source of ligand-free palladium in Heck reactions of aryl bromides.
Catalytic activity of Pd(II) and Pd(II)/DAB-R systems for the Heck arylation of olefins
Grasa, Gabriela A.,Singh, Rohit,Stevens, Edwin D.,Nolan, Steven P.
, p. 269 - 279 (2007/10/03)
Palladium-catalyzed reactions of aryl bromides with various olefins involving Pd(II)/diazabutadiene (DAB-R) systems have been investigated. The scope of a coupling process using Pd(II) sources and an α-diimine as ligand in the presence of Cs2CO3 as base was tested using various substrates. The Pd(OAc)2/ DAB-Cy (1, DAB-Cy=1,4-dicyclohexyl-diazabutadiene) system presents the highest activity with respect to electron-neutral and electron-deficient aryl bromides in coupling with electron rich olefins. The synthesis and X-ray characterization of a Pd(II)-diazabutadiene ligand is reported. Extensive optimization experiments showed that another Pd(II) source, Pd(acac)2 (acac=acetylacetonate), proved to activate aryl bromides at high temperatures, low catalyst loadings when the appropriate concentration of nBu4NBr additive was employed. The effect of the DAB-Cy ligand is important at very low catalyst loadings and high temperatures. Pd(acac)2 and Pd(acac)2 /DAB-Cy precatalysts were very effective for the arylation of various olefins with aryl bromides with respect to reaction rate, catalyst loadings, and functional group tolerance.
First palladium-catalyzed Heck reactions with efficient colloidal catalyst systems
Beller, Matthias,Fischer, Hartmut,Kuehlein, Klaus,Reisinger,Herrmann
, p. 257 - 259 (2007/10/03)
For the first time it has been shown that palladium colloids are effective and active catalysts for the olefination of aryl bromides (Heck reaction). Worthy of note are the high activities of the catalyst system for activated aryl bromides under optimized reaction conditions, which are better than or comparable with classical palladium phosphine complexes. Addition of phosphines strongly retards the reaction rate of the colloid catalyst. Nevertheless, this type of catalyst is not suitable for the activation of non-activated substrates, especially technically interesting aryl chlorides.
